This invention relates to improvements in wire strippers, such improvements being of particular benefit to the aircraft industry.
The improvement is particularly applicable to hand-held wire strippers of the type described in U.S. Pat. No. 2,523,936 and illustrated herein in FIGS. 1, 2, and 3.
In use, an insulated wire 1 is inserted into the jaw of the wire strippers and adjusted to lie within a suitably-sized notch 2. The handles 3 of the wire strippers are then squeezed together against the action of a spring 4. As the handles are drawn inwards, two members 5 and 6 move downwards to grip and cut, respectively, the insulation on the wire 1. As the handles are drawn further together, the shoulders 7 and 8 of the strippers move apart, carrying with them, respectively, the gripping member 5 and cutting member 6. (See FIG. 3). As the wire is still being gripped by the member 5 and the insulation has been cut, the unwanted piece of insulation 9 is pushed off the wire by the cutting member 6 and discarded. The grip on the handles 3 is then relaxed and the handles 3 are allowed to return to their original position under the action of the spring 4. During this final operation, the gripping and cutting members move upwards thus enabling the stripped wire to be removed from the wire strippers.
From the foregoing description, it will be apparent that the operator of the wire strippers has no means of controlling the flight of the severed insulation 9 as it is pushed away from the strippers. In current practice, the insulation is allowed to drop onto the floor of the operator's working area for later collection and disposal. This practice poses problems in the field of aircraft assembly.
During aircraft manufacture and assembly, large numbers of wiring looms require installation into the airframe assembly. These looms often comprise many cables which may need to be stripped in situ, inside an aircraft fuselage for example.
During aircraft assembly operations, it is essential that all foreign objects are removed from the airframe after each stage of assembly.
Foreign object damage (FOD) is a hazard well known to aircraft manufacturers and operators and stringent precautions must always be taken to reduce (and preferably, eliminate) the risk of FOD.
It will be appreciated that pieces of insulation left behind inside a fuselage after a wire-stripping operation, would constitute a FOD risk, jeopardising the safety of the aircraft and personnel.
Current practice, in this context is to visually locate and then remove all pieces of discarded insulation. Sometimes this operation is aided by inversion of the fuselage in question. Preferably, operators need to keep account of how many wires they have stripped.
It will be evident that this location and removal procedure is laborious. Another disadvantage is that it is not fail-safe.
This invention aims to obviate the need for said location and removal operation by providing a means for collection of the severed pieces of insulation. In particular, it provides such a means for collection which can be easily adapted for use with wire strippers of the type described above.
One known proposal for overcoming the afore-mentioned problems involves clamping the shoulders, 7 & 8 of the wire strippers so that their relative movement is severely limited. Using this method, the insulation, once cut remains on the wire. Also, the wire remains clamped by the member 5 until the operator relaxes his grip on the handles 3. He then removes the wire 1 from the strippers and pulls off the severed insulation. Although the operator can control removal of insulation, the procedure is time consuming. Furthermore, it is a two-handed operation.
The present invention provides a solution to the afore-mentioned problems which involves a quick, single-handed operation.